Keyboard construction for accor



Jan. 7, 1941. F. MAGNANTE KEYBOARD CONSTRUCTION FOR ACCORDIONS Filed May5, 1939 m I I \Mk WW a a Q 4. l m 7 W: W 0 0 .1 A. 3 27 &\ Z HA 2 a \r w7 9/7 2 W 1 2 1 JV Z 6 Z 0m fl n 4 .ZL/ wf Z Z v4 Z 5 F WW 3 a a a 1 B m0 a l w a 3 Z8 2 a z INVENTOR FRANCESCO MA GA/AA/Tf ATTORNEY PatentedJan. 7, 1941 PATENT OFFICE KEYBOARD CONSTRUCTION FOR ACCOR- DION SFrancesco MagnantaMilford, N. J.

Application May 5, 1939, Serial No. 271,917

5 Claims.

This invention relates to improvements in keyboards and moreparticularly to means for regulating the tension and movement of thekeys of accordions.

The action of the keys of an accordion, after some use, tends to change,becoming less springy and materially effecting the technique of theartist. This change in the action of the keys is also affected byweather changes. Heretofore, it has been quite inconvenient to regulatethis tension, it being necessary to practically disassemble the keyboardin order to make the required adjustments which, up to the present time,have been of the trial and error method entailing kinking of the actionsprings either by hand or with the aid of pliers. Heretofore, in orderto make these adjustments, it has been necessary to send the instrumentto the manufacturer or to some service establishment. It is obvious,then, that the adjustments could not be made at the time desired, by theartist himself.

Recognizing the above faulty construction of accordion keyboards, thepresent invention contemplates the provision of regulating means for theaction springs of the keys, said means being readily available so thatuniform regulation of the tension of said springs may be had quickly andwith a minimum of efiort. In this manner the artist may quickly and atthe time desired, adjust and regulate the key pressure to meet histastes and desires. He is able to vary this pressure from less than 4ounces to more than 6, giving him quite a large range in eitherdirection from the normal 4 ounces at which accordion keys are usuallyset. Inasmuch as the physical condition of the artist changes from timeto time, his technique would be deleteriously affected unless ascontemplated herein he were able to quickly make the aforementionedadjustments.

The movement of the keys are closely related to the tension thereof andthe invention, therefore, further contemplates means for regulating saidmovement or stroke to meet the desires of the user as to volume orloudness of sound and tone, since the length of the stroke of the keycontrols the extent to which the valves are opened to determine thevolume of the blast of air from the bellows of the instrument.

The invention is further characterized by the simplicity of itsconstruction and by the general convenient arrangement of the parts.

In the accompanying drawing a keyboard construction for accordions, asat present conceived, has been illustrated. The following specificationbased on said drawing will more clearly set forth the above and otherobjects, features and advantages of the invention.

In the drawing:

Fig. 1 is a transverse sectional view of an accordion keyboard showing awhite key construction.

Fig. 2 is a similar View showing the black key construction.

Fig. 3 is a fragmentary sectional view as taken along the line 33 ofFig. 1.

Fig. 4 is a similar fragmentary view taken through a medial portion ofthe keyboard.

Fig. 5is a fragmentary plan view of the keyboard with the keys removed.

In that preferred embodiment of the invention which is illustrated, thekeyboard [0 is formed with a series of key seats ll defined by the wallsI2. Certain of these key seats serve to accommodate the white keys [3which are pivoted upon a rod or pin l4 passing through apertures in thewalls l2. In the usual manner, each of the keys I3 is connected as bymeans of an arm I5 to a valve cover I6 operating against the orificescommunicating with a reed chamber. The key construction above outlinedis typical as is also the construction of the black keys [1. The latter,however, are pivoted upon a second pivot rod l8 carried by the walls I2in a manner similar to the rod I4.

Each of the white keys I3 is provided with means for maintaining itsvalve cover against the openings, in the reed chamber and providing aresilient counter-acting force against the manual pressure by the playeron said keys. In the present instance, this means comprises a spring l9formed with an eye 20 strung about a rod 2! also carried by the walls [2of the keyboard. In its present form the spring l9 comprises an arm 22having contact at its free end with the underside of the key I 3 andwith an arm 23 engaged against a plate 24 fixedly held to the keyboardat one end of said plate as by means of the screws 25. In order toposition the arm 23 of the spring [9 against inadvertent displacement,the free end of the plate 24 is formed with a V-shaped groove 26 inalignment with said arm 23.

It is evident from this construction that pressure on the key l3 will beresisted by the spring IS with a force which will vary with theresiliency of said spring. It is also evident that it is quite difficultto provide each of the springs 19 of each of the keys I3 with the sametension even upon initial assembly. For this reason, it is quitedesirable to provide means for regulating the tension of said springs souniformity of resistance thereof may be had. As shown in Fig. 1, forthis purpose, there is provided a regulating screw 21 accessible fromthe bottom or back of the keyboard and arranged to engage the free endof the plate 24 to move said free end of the plate and thus the arm 23of the spring l9. Setting the regulating screw 27 in will increase thetension on the spring l9 and slacking it off on said screw will reducethe tension. Thus it is possible in a few moments to accurately regulatethe tension of the action of all of the keys [3.

As shown in Fig 2, a similar construction is carried out for the blackkeys I! and the parts above described have been given similar referencenumbers, the only difference being that the spring ill, in this secondinstance, is strung on a rod 2m parallel to and spaced from the rod 2!.Although the second rod Zia is preferably used, it may be arranged tostring all of the springs [9 upon one rod.

The degree of rotation of each of the keys I3 may also be regulated. Forthis purpose, as shown in Figs. 1 and 3, the front bar 28 of thekeyboard may serve to carry, as by means of the screw seats 29, aplurality of set screws 30, in longitudinal arrangement. The upper endsof these said screws may be reduced for connection with a bar 3| commonto said screws and apertur d for the mentioned reduced portions so thatrotation of said screws may be had. It can be seen from the above, thatrotation of the screws 3a in their seats 29 will cause movement of thebar 3i either toward or from the lips [3a of the keys [3. The stroke ofthese keys may thus be readily and easily regulated. In the usual mannera felt bufier lining 32 upon the top of the bar 3| may be applied toobviate undue shock as the keys strike thereon.

While the foregoing key stroke regulating means is common for all of thewhite keys, it is apparent that each of the keys I 3.may be providedwith individual stroke regulating means. As an example of such aconstruction, resort may be had to the stroke regulating means of theblack keys (1 shown in Figs. 2 and 5, wherein each key is associatedwith a stop plate 33 carried upon a set screw 34 in the screw seat 35.Here also a felt buffer 36 on the plate 33 may be applied.

t will be noted from the foregoing that all of the regulator andadjusting means employed in this invention for varying the tension ofthe action and the degree of stroke of the keys, are readily and easilyaccessible from the back of the keyboard and such regulation may beaccomplished with a minimum of effort. The trial and error methodpreviously employed has been obviated and an eflicient and desirableconstruction provided. Inasmuch as many immaterial changes may be made,it is not desired to limit the scope of the invention as hereinafterclaimed, upon the instant specific disclosure.

What I claim as new and desire to secure by Letters Patent, is:

1. Accordion key tensioning means comprising a hairpin spring memberhaving its bight fixedly located relative to a key with one leg incontact with the key, and screw means adjustably associated with theother leg of the spring for regulating the tension of said spring.

2. Accordion key tensioning means comprising a hairpin spring memberhaving one leg in contact with the key, and means for regulating thetension of said spring comprising a flexible plate having contact withthe other leg of the spring and screw means for variably flexing saidplate.

3. In combination, an accordion base-board, a key mounted on saidbase-board for yieldingly controlled pivotal movement, and means forregulating the tension on said key comprising a hairpin spring memberhaving one end in contact with said key, a flexible plate carried bysaid base-board and having contact with the other end of said spring,and means threadedly connected with the base-board for variably flexingsaid plate.

4. In an accordion key-board construction, a base-board, a plurality ofkeys pivotally mounted on said base-board, a flexible plate secured tothe base-board under each key, means for tensioning each keyindividually, said means comprising a hairpin spring having one leg incontact with its respective key, and the other leg in contact with itsrespective flexible plate, means for regulating the tension of each key,said tension-regulating means comprising screw means carried by thebase-board for variably flexing said plate.

5. In an accordion key-board construction, a base-board, a plurality ofkeys pivotally mounted on the inner side of said base-board, means fortensioning each key individually, said means comprising a hair pinspring having its bight located on a fixed center and having one leg incontact with its respective key, and means for regulating the tension ofeach key, said tensionregulating means comprising screw means car riedby the base-board and accessible from the outer side thereof forvariably flexing the other leg of said spring.

FRANCESCO MAGNANTE.

